CN115443113A

CN115443113A - Shell for artificial joint and manufacturing method thereof

Info

Publication number: CN115443113A
Application number: CN202180029329.9A
Authority: CN
Inventors: 野田岩男
Original assignee: Kyocera Corp
Current assignee: Kyocera Corp
Priority date: 2020-04-22
Filing date: 2021-04-20
Publication date: 2022-12-06
Also published as: JPWO2021215441A1; AU2021260003B2; EP4140510A1; US20230240853A1; AU2021260003A1; WO2021215441A1; EP4140510A4

Abstract

The artificial joint shell of the present invention comprises: a cup-shaped substrate having an outer surface comprising a first region and a second region adjacent to the first region; and a coating film that is disposed so as to span the first region and the second region of the outer surface of the base body, and that includes a calcium phosphate-based material and an antibacterial material, wherein a surface roughness of a surface of the coating film in the first region is larger than a surface roughness of a surface of the coating film in the second region.

Description

Shell for artificial joint and manufacturing method thereof

Technical Field

The invention relates to a shell (shell) for an artificial joint and a manufacturing method thereof.

Background

The use of biological implants in the treatment of both skeletal injuries and diseases is constantly expanding as the population of sports and elderly people increases. Among them, from the viewpoint of antibacterial properties, adhesion to bones, and the like, a coated bioimplant is known.

For example, patent document 1 describes a coating for a medical implant, a part of which contains a bone cement and an antibacterial metal agent containing silver.

Prior art documents

Patent document

Patent document 1: JP 2011-512959 publication

Disclosure of Invention

The artificial joint shell of the present invention comprises: a cup-shaped substrate having an outer surface comprising a first region and a second region adjacent to the first region; and a coating film that is disposed so as to span the first region and the second region of the outer surface of the base, and that contains a calcium phosphate-based material and an antibacterial material. The surface roughness of the surface of the coating film in the first region is greater than the surface roughness of the surface of the coating film in the second region.

In addition, the method for manufacturing a shell for an artificial joint of the present invention includes: preparing a cup-shaped base; disposing a first protective material so as to expose a part of an outer surface of the base and protect another part of the outer surface; a first roughening step of forming a first rough surface portion on a portion exposed from the first protective material; removing the first protective material; and a coating film forming step of forming a coating film including a calcium phosphate-based material and an antibacterial material on at least a part of the first rough surface portion and the other part of the outer surface.

Drawings

Fig. 1 is a schematic view showing a state in which an artificial joint housing according to an embodiment is viewed from above.

Fig. 2 is a schematic view showing a state in which the artificial joint housing according to the embodiment is viewed obliquely from below.

Fig. 3 isbase:Sub>A schematic view showingbase:Sub>A cross section of the artificial joint housing of the embodiment cut atbase:Sub>A-base:Sub>A' of fig. 1.

Fig. 4 is a schematic diagram showing an example of a cross section of the artificial joint housing of the embodiment, the cross section being enlarged in the X region of fig. 3.

Fig. 5 is a schematic diagram showing an example of a cross section of the artificial joint housing of the embodiment, the cross section being enlarged in the X region of fig. 3.

Fig. 6 is a schematic diagram showing an example of a cross section of the artificial joint housing of the embodiment, the cross section being enlarged in the X region of fig. 3.

Fig. 7 is a schematic diagram showing an example of a cross section of the artificial joint housing of the embodiment, the cross section being enlarged in the X region of fig. 3.

Fig. 8 is a schematic diagram showing an example of a cross section of the artificial joint housing according to the embodiment cut at B-B' in fig. 1.

Fig. 9 is a schematic diagram showing an example of a cross section of the artificial joint housing according to the embodiment, the cross section being enlarged in the Y region of fig. 8.

Fig. 10 is a schematic view showing an artificial hip joint according to an embodiment.

Fig. 11 is a schematic view showing an example of a tool attached to the artificial hip joint shell according to the embodiment.

Fig. 12 is a schematic view showing an example of a tool attached to the artificial hip joint shell according to the embodiment.

Fig. 13 is a process diagram illustrating a method of manufacturing a shell for a joint according to an embodiment.

Detailed Description

Hereinafter, one embodiment will be described in detail. In the present specification, "a to B" indicating a numerical range means "a to B inclusive" unless otherwise specified.

[ 1. Casing for artificial joint ]

First, the structure of the artificial joint housing 130 according to an embodiment will be described with reference to fig. 1 to 4. Fig. 2 is a perspective view of the artificial joint housing 130. As shown in fig. 2, the artificial joint shell 130 has, for example, one hemispherical shape obtained by dividing a spherical member into two halves, and the coating film 20 is disposed on the outer surface of the hemispherical base 10. The coating film 20 contains a calcium phosphate material and an antibacterial material. The calcium phosphate-based material has an effect of improving the adhesiveness to bone. In addition, the antibacterial material has an effect of reducing adhesion and proliferation of bacteria.

The base 10 is a member in which a liner 120 described later is disposed. The base 10 has a cup shape having a concave portion including an opening 12 that opens in one direction of the base 10. As a result, the liner 120 is disposed in the base 10 through the opening 12. The base 10 of the present embodiment includes a layer member 30 between the outer surface and the coating film 20. The base 10 has a screw hole 31 and a spot facing 32. In the present invention, the base 10 may not have the layer member 30, the screw hole 31, and the spot facing 32.

In the present embodiment, as shown in fig. 2, the surface of the artificial joint case 130 corresponding to the cross section when the sphere is divided so as to include the center of the sphere is defined as an XY plane, and the direction perpendicular to the XY plane and toward the apex of the hemisphere is defined as a Z direction. The Z direction is referred to as the upper side of the artificial joint housing 130.

Fig. 1 is a schematic view showing a state in which the artificial joint case 130 is viewed from above. As shown in fig. 1, the artificial joint housing 130 has a hemispherical shape as described above. The base 10 has a hemispherical shape, and the outer surface of the base 10 has a first surface 301 (lower surface, see fig. 2) facing downward of the base 10 (negative direction of the Z axis) and a second surface 302 (outer peripheral surface, see fig. 2) different from the first surface 301. The first surface 301 defines the opening 12, and the second surface 302 is a surface that comes into contact with the pelvis during surgery. In the present embodiment, the first surface 301 is a flat surface, and the second surface 302 is a convex curved surface.

The cup shape of the substrate 10 may be, for example, a segment shape in which a region smaller than half is cut out from a ball or another segment shape in which a segment shape is cut out from a ball, in addition to the hemispherical shape formed by dividing a spherical member into two halves as described above. For example, the shape of a half ellipsoid divided so as to include the center of the ellipsoid, a cutout shape in which a region smaller than half is cut out from the ellipsoid, or the other of the cutout shapes cut out from the ellipsoid may be used.

The convex curved surface of second surface 302 may be convex when second surface 302 is captured over the entire area, or may have a portion that is partially concave. The convex curved surface of the second surface 302 may be a curved surface when captured in the entire region, and may be a partially flat surface. The inner surface of the concave portion of the base 10 has a concave curved surface. The inner surface may be recessed when captured in the entire region, or may be partially projected. The concave curved surface of the inner surface may be a curved surface when captured in the entire region, or may be a partially flat surface.

The opening 12 may be a straight line when the base 10 is viewed from the lateral side as shown in fig. 3, but may be a curved line protruding upward, a curved line protruding downward, or a wave having a portion protruding upward and/or a portion protruding downward twice or more.

The outer surface of the substrate 10 of the present embodiment includes the first region 1, the second region 2, and the third region 3. The substrate 10 of the present invention may not include the third region 3. The base 10 of the present embodiment is provided with the above-described screw hole 31 and countersink 32. In this case, the substrate 10 may further include the fourth region 4 and the fifth region 5. In the substrate 10 of the present invention, the fourth region 4 and the fifth region 5 may not be present.

The first region 1 is a region of the outer surface of the base 10, which is disposed in at least a part of the region other than the end of the second surface 302. When the screw hole 31 and the spot facing 32 are arranged in the base 10, the first region 1 is a region of the outer surface of the base 10, which is arranged in at least a part of the region excluding the end of the second surface 302 and the peripheries of the screw hole 31 and the spot facing 32.

The second region 2 is a region adjacent to the first region 1 and disposed between the first region 1 and the opening 12 of the base 10. The third region 3 is a region adjacent to the second region 2 and disposed between the second region 2 and the opening 12. The fourth region 4 is a region which is adjacent to the first region 1 and is disposed between the first region 1 and the screw hole 31 or the countersink 32. The fifth region 5 is a region adjacent to the fourth region 4 and disposed between the fourth region 4 and the screw hole 31.

The coating 20 is disposed so as to span the first region 1 and the second region 2 of the outer surface of the substrate 10, and the surface roughness of the surface of the coating in the first region 1 is greater than the surface roughness of the surface of the coating in the second region 2.

The coating 20 located in the second region 2 may have an end portion 21 and a base portion 22 located closer to the first region 1 than the end portion 21, and the thickness of the base portion 22 may be larger than that of the end portion 21.

When the third region 3 is disposed on the substrate 10, the outer surface of the substrate 10 located in the third region 3 is exposed from the coating film 20. And, the surface roughness of the surface of the coating film 20 in the second region 2 is larger than the surface roughness of the outer surface in the third region 3.

In addition, when the fourth region 4 is disposed on the substrate 10, the surface roughness of the outer surface located in the fourth region 4 is smaller than the surface roughness of the surface of the coating film in the first region 1. A coating film 20 is disposed on at least a part of the outer surface of the fourth region 4. When the fifth region 5 is disposed on the substrate 10, the entire outer surface of the fifth region 5 is exposed from the coating film 20.

Fig. 3 isbase:Sub>A view showingbase:Sub>A cross section of the artificial joint housing 130 cut atbase:Sub>A-base:Sub>A' of fig. 1. Fig. 4 to 7 are schematic views showing a state in which the region X in fig. 3 is enlarged.

When the substrate 10 has the first region 1 and the second region 2 arranged in this order, and the substrate 10 has the third region 3, the first region 1, the second region 2, and the third region 3 are arranged in this order as shown in fig. 4. It is understood that the first region 1 and the second region 2, or the first region 1, the second region 2, and the third region 3 are arranged in a direction parallel to the surface of the substrate 10. When the substrate 10 does not have the third region, the second region 2 corresponds to the end of the substrate 10 on the opening 12 side, and when the substrate 10 has the third region, the third region 3 corresponds to the end of the substrate 10 on the opening 12 side.

In fig. 4 to 7, the first region 1, the second region 2, and the third region 3 are hatched differently for convenience, but they need not be different members. The base body 10 may also be formed from one piece. The first region 1, the second region 2, and the third region 3 may be distinguished in design according to the presence or absence of a coating, a rough surface described later, or the like, for example. The coating film 20 is disposed so as to cross the first region 1 and the second region 2. The third region 3 is exposed from the coating film 20. Here, in the case where the base 10 has the third region 3, the surface roughness of the surface of the coating film 20 located in the first region 1 is larger than the surface roughness of the surface of the base 10 in the third region 3.

An example of the index of the surface roughness is arithmetic average roughness Sa (ISO 25178). The surface roughness (Sa) of the coating 20 located in the first region 1 may be set to, for example, 10 to 80 μm, 20 to 80 μm, or 30 to 70 μm. The surface roughness (Sa) of the substrate 10 in the third region 3 may be set to less than 1.0 μm, for example.

The surface roughness Sa of the first region 1 can be obtained from the measurement result of the entire first region 1. Similarly, the surface roughness Sa of the second region 2 can be determined from the measurement result of the entire second region 2, and the surface roughness Sa of the third region 3 can be determined from the measurement result of the entire third region 3. For example, in the first region 1, a portion having a surface roughness smaller than that of the substrate 10 in the second region 2 may be locally present, and in the second region 2, a portion having a surface roughness larger than that of the coating film 20 in the first region 1 may be locally present.

The surface roughness of the coating 20 or the surface roughness of the substrate 10 may be measured in a stylus type or optical type, for example. The surface roughness may be measured, for example, in accordance with "ISO 25178". The measurement of the surface roughness is not limited to the above method.

Here, conventionally, there has been room for improvement in an artificial joint shell from the viewpoint of achieving both antibacterial properties and control of adhesiveness to bone. That is, for example, when there is a region having a large surface roughness on the surface of the shell for an artificial joint, the end of the region having a large surface roughness may cause irritation to bone or soft tissue, and may become a starting point of bacterial infection.

According to the artificial joint housing 130 of the present invention, the surface roughness of the coating film 20 in the first region 1 is larger than the surface roughness of the coating film 20 in the second region 2. Therefore, the adhesiveness to the bone can be sufficiently ensured. Further, a coating film 20 is provided so as to span the first region 1 and the second region 2. Therefore, the end of the first region can be covered with the antibacterial coating film 20, and the shell 130 for an artificial joint can control both the adhesiveness to a bone and the antibacterial property.

Metals, ceramics or plastics may be used in the base body 10. Examples of the metal include stainless steel alloys, cobalt/chromium alloys, titanium and titanium alloys. As the titanium alloy, an alloy in which at least 1 kind of aluminum, tin, zirconium, molybdenum, nickel, palladium, tantalum, niobium, vanadium, platinum, and the like is added to titanium can be used. Examples of the ceramic include alumina, zirconia, and alumina/zirconia composite ceramics. Examples of the plastic include polyethylene, fluorine-based resins, epoxy resins, polyetheretherketone (PEEK) resins, and phenol resins. In the present embodiment, the substrate 10 is formed of a titanium alloy.

At least a part of the first region 1 is covered with the coating film 20. That is, the entire first region 1 may be covered with the coating 20, or only a part of the first region may be covered with the coating 20. In addition, the surface roughness of the surface of the coating film 20 located in the first region 1 is larger than the surface roughness of the surface of the coating film 20 in the second region 2. By providing the region having a large surface roughness in this manner, adhesiveness to bone can be improved. For example, by forming a rough surface in the first region 1 and covering the rough surface with the coating film 20, the surface roughness of the coating film 20 located in the first region 1 can be increased.

The surface roughness of the rough surface formed in the first region 1 is set to be larger than the surface roughness of the second region 2. Therefore, the surface roughness of the coating film 20 located in the first region 1 can be made larger than the surface roughness of the coating film 20 located in the second region 2. The surface roughness of the rough surface formed in the first region 1 may be set to 10 μm to 80 μm, or 20 μm to 80 μm, or 30 μm to 70 μm, for example. The surface roughness of the rough surface can be measured by, for example, cutting the case 130 for artificial joint and observing the cut surface by SEM or the like. The shell 130 for an artificial joint according to the present invention is not limited to the case where the surface roughness of the first region 1 is larger than the surface roughness of the second region 2.

The artificial joint housing 130 may further include a layered member 30. The layered member 30 may be disposed on the first region 1. Thereby, as shown in fig. 4, the first region 1 is higher than the region (for example, the second region 2) where the layer member 30 is not provided. Therefore, when the artificial joint housing 130 is embedded in a bone, the first region 1 can be mainly brought into contact with the bone. In the present specification, the "layered member" refers to a member different from the coating film 20, which is laminated on the base 10. For example, the surface of the layer member 30 may be roughened. This makes it possible to make the region mainly in contact with the bone a rough surface. As described later, the layered member 30 may be formed by a thermal spraying method. Alternatively, the layer member 30 may be formed in a porous structure. In the present embodiment, the surface roughness of the layered member 3 is set to be larger than the surface roughness of the second region 2.

The height of the layer member 30 may be set to, for example, a lower limit of 100 μm or more, or 300 μm or more. The upper limit may be set to 1000 μm or less, for example, and may be set to 700 μm or less. The surface roughness of the layered member 30 may be set to 10 μm to 80 μm, 20 μm to 80 μm, or 30 μm to 70 μm, for example.

Instead of providing the layer member 30, the base 10 may be formed in a shape that allows the first region 1 to mainly contact the bone. For example, the first region 1 may be raised with respect to the second region 2 and the third region 3.

As the material of the layer member 30, the material exemplified as the material of the base 10 can be used. For example, the layered member 30 may be made of metal. The material of the layered member 30 and the material of the base 10 may be the same material, but may be different. This ensures sufficient strength. In the present embodiment, the layered member 30 is formed of the same material as the base 10. In the present embodiment, the layered member 30 is formed of a titanium alloy.

The layered member 30 may also have edges that are of a lower height than the interior of the layered member 30. In the present specification, "inside of the layered member" means the inside in the plane direction of the layered member 30. Fig. 5 shows a laminate member 30 having an edge of lower height than the interior. This can reduce concentration of stress on the edge of the layered member 30.

The coating film 20 contains a calcium phosphate material and an antibacterial material. As the calcium phosphate-based material, for example, a mixture of 1 or 2 or more selected from the group consisting of hydroxyapatite, α -tertiary calcium phosphate, β -tertiary calcium phosphate, quaternary calcium phosphate, octacalcium phosphate, and calcium phosphate-based glass can be used. As the antibacterial material, a natural antibacterial agent, an organic antibacterial agent, or an inorganic antibacterial agent can be used. Examples of the natural antibacterial agent include hinokitiol, the organic antibacterial agent includes benzalkonium chloride, the inorganic antibacterial agent includes a metal, and the metal includes silver, copper, zinc, and the like. The coating film 20 may contain glass ceramics, as well as calcium phosphate-based materials and antibacterial materials, and may also contain antibacterial agents such as penicillin and vancomycin.

The concentration of the antimicrobial material in the coating film 20 may be, for example, 0.05 wt% to 3.00 wt%, 0.05 wt% to 2.50 wt%, 0.05 wt% to 1.00 wt%, or 0.1 wt% to 1.00 wt%. When the concentration of the antibacterial material is 0.05 wt% or more, sufficient antibacterial properties can be obtained. In addition, if the concentration of the antibacterial material is 3.00 wt% or less, the burden on the living tissue can be reduced.

The coating film 20 may be disposed on the layered member 30. As described above, the layered member 30 can be primarily in contact with bone. By providing the coating film 20 on the layered member 30, the adhesiveness to bone and antibacterial properties can be further improved.

The height of the layered member 30 may also be greater than the thickness of the cover film 20. Thus, the region in which the layer member 30 is formed is higher than the region in which only the coating film 20 is formed, and therefore, the region in which the layer member 30 is formed can be mainly brought into contact with the bone. The thickness of the coating 20 may be set to less than 100 μm, for example, and may be set to less than 50 μm. The thickness of the coating film 20 may be set to 5 μm or more, for example.

At least a part of the second region 2 is covered with the coating film 20. That is, the entire second region 2 may be covered with the coating 20, or only a part of the second region may be covered with the coating 20. In the present specification, the phrase "the coating film 20 spans the first region and the second region" means that at least a part of the boundary between the first region 1 and the second region 2 is covered with the coating film 20. That is, the boundary between the first region 1 and the second region 2 may be entirely covered with the coating 20, or may be covered with only a part of the coating 20. When the layer member 30 is disposed in the first region 1, the coating film 20 may extend from the first region 1 to the second region 2 so as to cover the edge of the layer member 30. That is, the edge of the layered member 30 can be prevented from being exposed from the coating film 20. This can further reduce the growth of bacteria.

The coating film 20 located in the second region 2 may have an end portion 21 and a base portion 22 located closer to the first region 1 than the end portion 21. In the present specification, the term "end portion of the coating film located in the second region" refers to a region of the coating film 20 located in the second region 2, which is located on a side close to the boundary between the second region 2 and the third region 3. The term "base of the coating located in the second region" refers to a region of the coating 20 located in the second region 2, which is located on a side close to the boundary between the first region 1 and the second region 2. Here, the thickness of the base portion 22 may be larger than that of the end portion 21. Fig. 6 shows the coating 20 with a base portion 22 having a thickness greater than the thickness of the end portion 21. This can reduce concentration of stress in the vicinity of the boundary between the first region 1 and the second region 2, and as a result, peeling of the coating film 20 can be reduced. When the layer member 30 is disposed in the first region 1, concentration of stress in the vicinity of the edge of the layer member 30 can be reduced.

The third region 3 is exposed from the coating film 20. The portion where the coating film 20 is disposed and the portion exposed from the coating film 20 can be identified by elemental analysis of the surface of each region. The method of elemental analysis can be implemented by mapping surface elements using an energy dispersive X-ray analysis (EDX) device as an accessory to a typical Scanning Electron Microscope (SEM), for example. Further, surface analysis methods such as X-ray photoelectron spectroscopy, auger electron spectroscopy, secondary ion mass spectrometry, and the like may be used. Further, the elements may be confirmed by chemically analyzing a sample obtained by mechanically removing the surface of each region. For example, phosphorus, calcium, an antimicrobial component, and the like are detected on the surface of at least a part of the first region 1 and at least a part of the second region 2 where the coating film 20 is disposed. Elements constituting the substrate 10 are detected on the surface of the third region 3, and phosphorus, calcium, an antibacterial component, or the like is not detected, or phosphorus, calcium, an antibacterial component, or the like is equal to or lower than a noise level.

The surface roughness of the surface of the coating 20 located in the second region 2 may also be smaller than the surface roughness of the surface of the coating 20 located in the first region 1. Fig. 7 shows a mode in which the surface roughness of the coating film 20 located in the second region 2 is smaller than the surface roughness of the coating film 20 located in the first region 1. This ensures sufficient adhesiveness to bone and antibacterial properties in the first region 1. In addition, in the second region 2, physical stimulation to soft tissue can be reduced.

The surface roughness (Sa) of the coating film 20 located in the first region 1 may be set to, for example, 10 μm to 80 μm, 20 μm to 80 μm, or 30 μm to 70 μm. The surface roughness (Sa) of the coating film 20 located in the second region 2 may be set to 0.1 μm to 10 μm, for example.

In addition, the surface roughness of the surface of the coating film 20 located in the second region 2 may be larger than the surface roughness of the outer surface of the substrate 10 in the third region 3. Fig. 7 is a diagram illustrating a mode in which the surface roughness of the coating film 20 located in the second region 2 is larger than the surface roughness of the base 10 in the third region 3. In the second region 2, the adhesiveness between the coating film 20 and the base 10 is improved, and therefore, the adhesiveness to bone and the antibacterial property can be sufficiently ensured. In addition, in the third region 3, physical stimulation to soft tissue can be reduced. The surface roughness (Sa) of the substrate 10 in the third region 3 may be set to be less than 1 μm, for example.

As shown in fig. 7, the surface roughness of the outer surface of the substrate 10 in the second region 2 may be larger than the surface roughness of the outer surface of the substrate 10 in the third region 3. This improves the adhesion between the coating 20 and the substrate 10 in the second region 2, and can reduce peeling of the coating 20. The surface roughness (Sa) of the substrate 10 in the second region 2 may be set to 0.1 μm or more and less than 10 μm, or may be set to less than 2.0 μm.

In addition, in the present embodiment, the surface roughness of the rough surface of the substrate 10 (including the rough surface of the layer-shaped member 30) in the first region 1 is set to be larger than the surface roughness of the substrate 10 in the third region 3.

Fig. 8 is a view showing a cross section of the artificial joint housing 130 cut at B-B' of fig. 1. Fig. 9 is a schematic diagram showing a state in which the Y region in fig. 8 is enlarged. As shown in fig. 9, the width of the through portion 321 (second through portion) on the outer surface side of the spot facing 32 is smaller than the width of the through portion 322 (first through portion) on the opening 12 side. That is, the spot facing 32 includes a through portion 322 and a through portion 321 which is connected to the through portion 322 and the outer surface and has a width smaller than that of the through portion 322.

That is, the base 10 may have at least one through hole (screw hole 31, countersink 32) penetrating the outer surface and the inner surface (opening 12 side) of the base 10. At least one of the through holes (the screw hole 31) is disposed at a position farther from the opening 12 than the other position (the spot facing 32). The spot facing 32 as another through hole may include a through portion 322 and a through portion 321 which is connected to the through portion 322 and the outer surface and has a width smaller than that of the through portion 322.

The shell 130 for an artificial joint may have one or more fins.

[ screw hole 31 and countersink 32 ]

The threaded hole 31 is used, for example, to connect an instrument to the joint prosthesis housing 130 at the time of surgery. For example, as shown in fig. 11, by fixing the distal end portion of the holder 310 to the screw hole 31 of the artificial joint housing 130, the artificial joint housing 130 can be held by the holder 310 and the artificial joint housing 130 can be moved to a desired position.

The spot facing 32 may be used to fix the artificial joint shell 130 to the hip bone 93 with a screw 320, as shown in fig. 12, for example.

With the above configuration, the artificial joint housing 130 of the present invention has a rough surface, and thus can further improve bone conductivity and bone fixation. Further, since the coating film covers the rough surface portion so that the end portion thereof is not exposed, it is possible to prevent bacteria from growing from the end portion of the rough surface portion.

Further, the edge portion of the cup shape to which stress is easily applied is not roughened, and physical irritation to soft tissues can be reduced. Further, by lowering the edge of the case by one step, the irritation at the edge portion can be reduced.

Further, since the layered member is made of metal, sufficient strength can be secured, and by providing a coating film on the layered member, adhesion to the bone and antibacterial properties can be further improved.

Further, since the end portions of the metal layer are lower in height than the inside, stress concentration at the end portions of the rough surface portions can be prevented.

In addition, the peeling of the overcoat from the end portion can be prevented.

In addition, since the second region 2 sufficiently secures adhesiveness to bone and antibacterial property and the surface roughness of the third region 3 is small, irritation to soft tissue can be further alleviated.

Further, by providing the coating on the outer surface of the base 10 in the second region having a surface roughness greater than that of the outer surface of the base 10 in the third region 3, the coating adheres well to the base, and the coating is less likely to peel off from the base.

In addition, it can be fixed to the jig or the acetabulum at a desired position.

When the screw hole 31 and the spot facing 32 are arranged in the base 10, the first region 1, the fourth region 4, the screw hole 31, and the spot facing 32 are arranged in this order on the base 10. When the base 10 has the fifth region 5, the first region 1, the fourth region 4, the fifth region 5, and the screw hole 31 are arranged in this order on the base 10.

It is understood that the first region 1, the fourth region 4, the screw hole 31 or the spot facing 32, or the first region 1, the fourth region 4, the fifth region 5 and the screw hole 31 are arranged in this order in a direction parallel to the surface of the base 10. Therefore, when the substrate 10 does not have the fifth region 5, the fourth region 4 corresponds to the end of the substrate 10 on the screw hole 31 and the spot facing 32 side. In the case where the substrate 10 has the fifth region 5, the fifth region 5 corresponds to the end of the substrate 10 on the screw hole 31 side, and the fourth region 4 corresponds to the end of the substrate 10 on the spot facing 32 side.

The entire fourth region may be covered with the coating 20, or only a part of the fourth region may be covered with the coating 20. The boundary between the first region and the fourth region may not be covered with the coating film 20, but may be entirely covered with the coating film 20 or only partially covered with the coating film 20. When the boundary between the first region and the fourth region 4 is covered with the coating film 20, the coating film 20 can extend from the first region 1 to the fourth region 4 so as to cover the edge of the layer-shaped member 30 when the layer-shaped member 30 is disposed in the first region 1. That is, the edge of the layered member 30 can be prevented from being exposed from the coating film 20. This can further reduce the growth of bacteria.

The fifth region 5 is exposed from the coating film 20. The portion where the coating film 20 is disposed and the portion exposed from the coating film 20 can be identified by elemental analysis of the surface of each region. The method of elemental analysis can be implemented by mapping surface elements using an energy dispersive X-ray analysis (EDX) device as an accessory to a typical Scanning Electron Microscope (SEM), for example. Further, surface analysis methods such as X-ray photoelectron spectroscopy, auger electron spectroscopy, secondary ion mass spectrometry, and the like may also be used. Further, the elements may be confirmed by chemically analyzing a sample obtained by mechanically removing the surface of each region. For example, phosphorus, calcium, an antibacterial component, and the like are detected on the surface of at least a part of the first region 1 and at least a part of the fourth region 4 where the coating film 20 is disposed. Elements constituting the substrate 10 are detected on the surface of the fifth region 5, and phosphorus, calcium, an antibacterial component, or the like is not detected, or phosphorus, calcium, an antibacterial component, or the like is equal to or lower than a noise level.

The surface roughness of the surface of the coating 20 located in the fourth region 4 may also be smaller than the surface roughness of the surface of the coating 20 located in the first region 1. This can reduce physical stimulation to soft tissue in the fourth region 4.

The surface roughness (Sa) of the coating 20 located in the fourth region 4 may be set to, for example, 0.1 μm to 10 μm.

In addition, the surface roughness of the surface of the coating film 20 located in the fourth region 4 may be larger than the surface roughness of the outer surface of the base 10 in the fifth region 5. The surface roughness (Sa) of the substrate 10 in the fifth region 5 may be set to be less than 1 μm, for example.

In addition, the surface roughness of the outer surface of the base 10 in the fourth region 4 may be made larger than the surface roughness of the outer surface of the base 10 in the third region 3 or the fifth region 5. In the fourth region 4, the adhesiveness between the coating 20 and the substrate 10 is improved, and peeling of the coating 20 can be reduced. The surface roughness (Sa) of the substrate 10 in the fourth region 4 may be set to 0.1 μm or more and less than 10 μm, or may be set to less than 2.0 μm.

[ 2. Method for manufacturing case for artificial joint ]

The method for manufacturing a shell for a prosthetic joint of an embodiment includes: preparing a cup-shaped base; a step (S101) of disposing a first protective material so as to expose a part of the outer surface of the base and protect the other part of the outer surface; a first roughening step (S102) of forming a first rough surface portion on a portion exposed from the first protective material; a step (S103) of removing the first protective material; and a coating film forming step (S108) of forming a coating film (20) containing a calcium phosphate-based material and an antibacterial material on the first rough surface portion and at least a part of the other portion of the outer surface.

As a result, the artificial joint shell described above can be obtained in which the coating 20 is disposed so as to span the first region 1 and the second region 2, and the surface roughness of the surface of the coating 20 located in the first region 1 is greater than the surface roughness of the surface of the base 10 in the second region 2.

When a metal is used as the material of the cup-shaped base, the base can be formed by molding such as casting, plastic working, or sintering. After the formation by the molding step, the shape may be further adjusted by a removal process such as cutting, grinding, or electric discharge machining. The screw hole 31 or the spot facing 32 may be formed by molding or may be formed by removing without molding.

In the first roughening step, the roughened surface may be formed by at least one of a thermal spraying method, a lamination method, a chemical etching method, and a spraying method. The thermal spraying method, the lamination molding method, or the chemical etching method can increase the surface roughness as compared with the spraying method. As the thermal spraying material and the laminate molding material, materials exemplified as the material of the substrate 10 can be used. The above-mentioned layered structure may be formed by a thermal spraying method or a lamination molding method. The chemical etching method may include alkali treatment. Examples of the blasting method include sand blasting. The formation of the rough surface may be performed before the formation of the coating film 20.

The film 20 can be formed by a thermal spraying method such as flame spraying, high-speed flame spraying, or plasma spraying. The deposition can also be performed by a physical vapor deposition method such as sputtering, ion plating, ion beam vapor deposition, or ion mixing method, or a chemical vapor deposition method. Alternatively, the coating may be performed by a wet coating method such as a sol-gel method.

A protective material may be used to form the rough surface or the coating film 20 only in a desired region. For example, masking tape (masking tape) or a spacer may also be used as the protective material. Alternatively, a jig covering the substrate 10 may be used as the protective material. Examples of the material of these protective materials include metal, glass, resin, and a composite material thereof.

The protective material may or may not be in contact with the substrate 10. When the protective material does not contact the substrate 10, the thermal spray material, the coating material, or the like may extend from the end of the protective material and may adhere to a region covered with the protective material to some extent. Thus, as described above, the coating film 20 or the like having a thickness of the layer member 30 and/or the base portion 22 having a lower edge than the inner portion and a thickness larger than the end portion 21 can be formed. As the protective material, for example, a masking tape having adhesiveness and capable of being stuck to the base 10 or a jig for covering the base 10 described later can be used.

When the separator is disposed, the rough surface or the coating film 20 can be formed in a specific region by moving the position of the separator every time the rough surface or the coating film 20 is formed. When a jig is used, the rough surface or the coating 20 can be formed in a specific area by changing the area covered with the jig every time the rough surface or the coating 20 is formed. In this case, for example, by adjusting the positional relationship between the discharge nozzle that discharges the thermal spray material or the coating material and the partition plate, the rough surface or the coating 20 can be selectively formed only in a desired region. In this case, the tip of the discharge nozzle may be arranged in a straight line without interposing a partition plate between the tip and the surface of a desired region, for example. The coating material is a material constituting the coating film. In the first roughening step, the surface of the first region 1 and the tip of the discharge nozzle may be arranged on a straight line without a partition plate. In the coating film forming step, the surface of the region spanning the first region 1 and the second region 2 and the tip of the discharge nozzle may be arranged on a straight line without a partition plate. When the screw hole 31 and/or the spot facing 32 are provided in the base 10, the surfaces of the first region 1, the second region 2, and the fourth region 4 and the nozzle tip may be arranged in a straight line without interposing a partition plate therebetween. In the case where the coating film 20 is formed simultaneously in the first region 1 and the second region 2, the discharge nozzle tip may be arranged on a straight line with the surface of the first region 1 without a partition, for example, in consideration of the diffusion of the material. The present invention is not limited to this, and the rough surface or the coating 20 may be formed in a state where the substrate 10, the partition plate, and the discharge nozzle are fixed, or the rough surface or the coating 20 may be formed while at least one of the substrate 10, the partition plate, and the discharge nozzle is moved. The angle of the nozzle may be fixed, or the rough surface or the coating film 20 may be formed while changing.

The rough surface or the coating film 20 can be formed only in a desired region without using a protective material. For example, the rough surface or the coating film 20 may be selectively formed only in a desired region by adjusting the shape, angle, position, or the like of a nozzle that discharges the thermal spray material or the coating material. For example, the thermal spraying material or the coating material may be discharged in a state where the discharge nozzle is positioned above the surface of the desired region. In the first roughening step, the thermal spray material may be discharged with the discharge nozzle positioned above the surface of the first region 1. In the coating film forming step, the coating material may be discharged with the discharge nozzle positioned above the surface of the region spanning the first region 1 and the second region 2. When the screw hole 31 and/or the spot facing 32 are provided in the base 10, the coating material may be discharged from the discharge nozzle in a state of being positioned above the surfaces of the region spanning the first region 1 and the second region 2 and the fourth region 4. In this case, the substrate 10 may be fixed to form the rough surface or the coating 20 while changing the position and the angle of the discharge nozzle, or the discharge nozzle may be fixed to form the rough surface or the coating 20 while changing the position and the angle of the substrate 10. The nozzle may be moved at a constant speed or may be moved at a variable speed. The discharge direction of the thermal spray material or the coating material may be at an angle of 90 ° or less with respect to a vector extending from the tip of the discharge nozzle toward the surface of the substrate 10 or the roughened surface located at the shortest distance from the tip of the discharge nozzle.

For example, in the first roughening step, the first protective material may be disposed on the substrate 10 so as to expose the first regions 1 and protect the second regions 2, and a roughened surface may be formed on the exposed first regions 1. When the screw hole 31 and/or the spot facing 32 are provided in the base 10, the first protective material may be disposed so as to expose the first region 1 and protect the second region 2, the fourth region 4, and the fifth region 5, and a rough surface may be formed in the exposed first region 1.

The manufacturing method of the present invention may further include a step of removing the first protective material after the first roughening step and before the coating film forming step.

After the first protective material is removed, a step of removing the edge of the rough surface, for example, the edge of the layer member 30 may be performed. This can avoid stress concentration at the edge of the layered member 30, thereby reducing irritation to the living tissue.

As the first protective material, a first masking tape may also be used. In this case, the manufacturing method of the present invention may further include a step of attaching the first masking tape to the second region 2 while exposing the first region 1, prior to the first roughening step. When the screw hole 31 and/or the spot facing 32 are provided in the base 10, a step of attaching the first masking tape to the second region 2, the fourth region 4, and the fifth region 5 while exposing the first region 1 may be further included.

The manufacturing method of the present invention further includes, after the step of removing the first protective material and before the step of forming the coating film: a step (S104) of disposing a second protective material so as to expose a part of the other part of the outer surface and protect the remaining part of the other part of the outer surface; and a second roughening step (S105) of forming a second rough surface portion on at least a part of the other part of the outer surface, wherein the second rough surface portion may be formed on the part exposed from the second protective material. In addition, a process of removing the second protective material (S106) may be further included after the second roughening process.

In the second roughening step, a rough surface may be formed by at least one of a chemical etching method and a blasting method. The second roughening process may be performed such that the surface roughness of the surface of the second rough surface portion formed in the second roughening process is smaller than the surface roughness of the surface of the first rough surface portion in the first region 1. When the second rough surface portion is formed, the rough surface in the first region 1 may be referred to as a first rough surface portion.

As the second protective material, a second masking tape may also be used. In this case, the manufacturing method of the present invention may further include, before the second roughening step, a step of exposing the first region 1 and the second region 2 and attaching the second masking tape to the third region 3. When the screw hole 31 and/or the spot facing 32 are provided in the base 10, a step of attaching a masking tape to the third region 3 and the fifth region 5 while exposing the first region 1 and the fourth region 4 may be further included.

The manufacturing method of the present invention further includes, after the step of removing the second protective material and before the step of forming the coating film: and disposing a third protective material so as to expose a part of the first rough surface portion and the second rough surface portion and protect the other part of the second rough surface portion and the outer surface (S107). In this way, in the coating film forming step, the coating film can be formed on the first rough surface portion and the second rough surface portion exposed from the third protective material. When the base 10 is provided with the screw hole 31 and/or the spot facing 32, the present invention further includes: and disposing a third protective material so as to expose a part of the second rough surface portion and the fourth region 4 and protect the other part of the second rough surface portion, the fifth region 5, and the outer surface (S107). In this way, in the coating film forming step, the coating film can be formed on the first rough surface portion, a part of the second rough surface portion, and the fourth region 4 exposed from the third protective material.

As the third protective material, a third masking tape may also be used. In this case, the manufacturing method of the present invention may further include, before the coating film forming step, a step of exposing a part of the first region 1 and the second region 2 and attaching the third masking tape to another part of the second region 2. When the screw hole 31 and/or the spot facing 32 are provided in the base 10, a step of exposing a part of the first region 1 and the second region 2 and a fourth region and attaching a masking tape to the other part of the second region 2 and the fifth region 5 may be further included.

The manufacturing method of the present invention may further include a hole forming step of forming a hole in the substrate in the step of preparing the substrate.

In the second roughening process, the first region 1 may be covered with a protective material or may not be covered with the protective material. The first region 1 may be protected, and only the second region 2 may be subjected to at least one of processing by a chemical etching method and processing by a sputtering method. When the screw hole 31 and/or the spot facing 32 are provided in the substrate 10, at least one of the chemical etching and the injection may be performed on the second region 2 and the fourth region. Alternatively, the second protective material may be disposed so as to expose the first region 1, and at least one of the chemical etching process and the blasting process may be performed on the exposed rough surface of the first region 1 and the second region 2. When the screw hole 31 and/or the spot facing 32 are provided in the substrate 10, at least one of the chemical etching and the injection may be performed on the rough surface of the first region 1, the second region 2, and the fourth region. Accordingly, it is possible to remove excess thermal spray material remaining on the rough surface of the first region 1, form a rough surface in the second region 2, and form a rough surface in the second region 2 and the fourth region even when the screw hole 31 and/or the spot facing 32 are provided in the substrate 10.

It should be noted that the second rough surface portion can be formed only in a desired region without using a protective material. For example, the second rough surface portion may be selectively formed only in a desired region by adjusting the shape, angle, position, or the like of a discharge nozzle that discharges a chemical etching material or a spray material. The chemical etching material is a material that is ejected toward the substrate 10 when processing is performed by a chemical etching method. Similarly, the ejection material is a material ejected toward the substrate 10 when processing by the ejection method is performed. For example, the chemical etching material or the spray material may be discharged in a state where the discharge nozzle is located at a position higher than the surface of the desired region. When the second rough surface portion is formed only in the second region 2, the chemical etching material or the spray material may be sprayed in a state where the spray nozzle is positioned in the upper direction than the surface of the second region 2. When the second rough surface portion is formed in the first region 1 and the second region 2, the chemical etching material or the spray material may be sprayed in a state where the spray nozzle is positioned above the surface of the first region 1 and the second region 2. When the screw hole 31 and/or the spot facing 32 are provided in the substrate 10 and the second rough surface portion is formed in the first region 1, the second region 2, and the fourth region 4, the chemical etching material or the spray material may be sprayed in a state where the spray nozzle is positioned in the upper direction than the surfaces of the first region 1, the second region 2, and the fourth region 4. In this case, the substrate 10 may be fixed to form the second rough surface portion while changing the position and angle of the discharge nozzle, or the discharge nozzle may be fixed to form the second rough surface portion while changing the position and angle of the substrate 10. The nozzle may be moved at a constant speed or may be moved at a variable speed. Further, the discharge direction of the chemical etching material or the spray material may be at an angle of 90 ° to a vector extending from the tip of the discharge nozzle toward the surface of the substrate 10 or the roughened surface at the shortest distance from the tip of the discharge nozzle, or may be at an angle of less than 90 °.

For example, a thermal spraying method may be used in the first roughening step and the coating film forming step, and a spraying method may be used in the second roughening step. In this case, as the first protective material, a material having higher heat resistance than the second protective material can be used. In addition, as the first protective material, a material having higher heat resistance than the third protective material can be used. In addition, as the third protective material, a material having higher heat resistance than the second protective material can be used. In order to satisfy such a relationship, for example, a material that does not dissolve or thermally decompose within 1 minute under the thermal spray condition of 8000 ℃, a material that does not dissolve or thermally decompose within 1 minute under the thermal spray condition of 3000 ℃, and a material that does not dissolve or thermally decompose at room temperature may be used as the first protective material, the third protective material, and the second protective material. As such a material, specifically, a composite material of glass and resin is used as the first protective material, a composite material of glass and resin is used as the third protective material, and resin is used as the second protective material.

When a jig for covering the substrate 10 is used as the protective material, the shape of the jig is not particularly limited, and the jig may be, for example, a cylindrical shape. The cross section of the cylindrical jig may be polygonal or circular.

To summarize the above, the steps may be performed in the order shown in fig. 13, for example. Fig. 13 is a process diagram illustrating a method of manufacturing the artificial joint housing according to the embodiment. First, a first protective material may be disposed, followed by a first roughening process, and then the first protective material may be removed. Then, a second protective material may be disposed, followed by a second roughening process, and then the second protective material may be removed. Then, a third protective material may be disposed, followed by a coating film forming process.

The production method of the present invention may or may not include a cleaning step between the steps. For example, the manufacturing method of the present invention may include a step of cleaning the substrate 10, or the substrate 10 and the layer member 30 disposed on the first region 1, after the first roughening step. After the second roughening step, a step of cleaning the substrate 10, or the substrate 10 and the layer member 30 disposed on the first region 1 may be included. The cleaning method is not particularly limited, and for example, the cleaning method may be a method of immersing the substrate in a liquid such as water or an organic solvent such as alcohol, or may be a method of spraying the liquid. Alternatively, a gas such as air, nitrogen, or argon may be blown. This makes it possible to remove the excess sprayed material and the like generated in the first roughening step and/or the cutting residue and the like generated in the second roughening step.

[ 3. Utilization of casing for artificial joint ]

The artificial joint shell 130 shown in fig. 1 is mainly assumed to have the shape of an artificial hip joint shell, but an artificial joint to which the artificial joint shell of the present invention is applied is not limited to an artificial hip joint. Examples of the artificial joint include an artificial hip joint, an artificial shoulder joint, and an artificial elbow joint.

An example in which the artificial joint shell 130 is used as a part of the artificial hip joint 1000 will be described below with reference to fig. 10. The artificial hip joint 1000 may include an artificial joint stem 100, a bone 110, and a liner 120 in addition to the artificial joint shell 130. The stem 100 and the bone 110 may be formed of the same material as the base 10 of the artificial joint shell 130 or may be formed of different materials. The artificial joint stem 100 is embedded in the femur 91. The bone 110 is disposed on the exposed portion of the artificial joint stem 100. The artificial joint shell 130 is fixed to the hip socket 94 of the hip bone 93, and the bone 110 is fitted into the recess of the artificial joint shell 130 and slid, thereby functioning as a hip joint. More specifically, the bone 110 is fitted into and slid in a recess of the liner 120 in the opening 12 of the artificial joint shell 130, thereby functioning as a hip joint.

The invention disclosed above is explained based on the drawings and the embodiments. However, the invention of the present disclosure is not limited to the above embodiments. That is, the invention of the present disclosure can be variously modified within the scope of the present disclosure, and embodiments obtained by appropriately combining technical means disclosed in the respective different embodiments are also included in the technical scope of the invention of the present disclosure. That is, it should be noted that various modifications and corrections are easy to make by those skilled in the art based on the present disclosure. In addition, it should be noted that these variations or modifications are included in the scope of the present disclosure.

Description of reference numerals:

a first region;

a second region;

a third region;

a fourth region;

a fifth region;

a substrate;

coating a film;

an end of the membrane;

a base of the overlay film;

a laminar member;

a stem for an artificial joint;

bone;

a liner;

a shell for a prosthetic joint;

an artificial hip joint.

Claims

1. A shell for an artificial joint, wherein,

the artificial joint shell is provided with:

a cup-shaped substrate having an outer surface comprising a first region and a second region adjacent to the first region; and

a coating film that is disposed so as to span the first region and the second region in the outer surface of the base body, and that contains a calcium phosphate-based material and an antibacterial material,

the surface roughness of the surface of the coating film in the first region is greater than the surface roughness of the surface of the coating film in the second region.

2. The shell for an artificial joint according to claim 1,

the second region is disposed between the first region and the opening of the base.

3. The shell for an artificial joint according to claim 2,

the base body further includes a layered member disposed in the first region.

4. The shell for an artificial joint according to claim 3,

the layered member is composed of metal.

5. The shell for an artificial joint according to claim 3 or 4,

the coating film disposed in the first region is disposed on the layered member.

6. The shell for an artificial joint according to any one of claims 3 to 5,

the laminar member has an edge that is lower in height than an interior of the laminar member.

7. The shell for an artificial joint according to any one of claims 2 to 6,

the coating film located in the second region has an end portion and a base portion located closer to the first region than the end portion,

the thickness of the base is greater than the thickness of the end.

8. The shell for an artificial joint according to any one of claims 2 to 6,

the outer surface of the base further has a third region adjacent to the second region and located between the second region and the opening portion,

the outer surface of the base located in the third region is exposed from the coating film.

9. The shell for an artificial joint according to claim 8,

the surface roughness of the surface of the coating film in the second region is greater than the surface roughness of the outer surface in the third region.

10. The shell for an artificial joint according to any one of claims 2 to 9,

the surface roughness of the outer surface in the first region is greater than the surface roughness of the outer surface in the second region.

11. The shell for an artificial joint according to claim 8 or 9,

the surface roughness of the outer surface in the second region is greater than the surface roughness of the outer surface in the third region.

12. The shell for an artificial joint according to any one of claims 2 to 11,

the base body has at least one through-hole penetrating the outer surface and the inner surface of the base body.

13. The shell for an artificial joint according to claim 12,

the outer surface of the base further has a fourth region adjacent to the first region and located between the first region and the through hole,

the surface roughness of the outer surface located in the fourth region is smaller than the surface roughness of the surface of the coating film in the first region.

14. The shell for an artificial joint according to claim 13,

at least one of the through holes is a screw hole disposed at a position farther from the opening than the through holes at other positions,

at least one of the other through holes is a spot facing having a first through portion and a second through portion connected to the first through portion and the outer surface and having a width smaller than that of the first through portion.

15. The shell for an artificial joint according to claim 14,

the coating film is disposed on at least a part of the outer surface in the fourth region.

16. The shell for an artificial joint according to claim 14 or 15,

the outer surface of the base further having a fifth region adjacent the fourth region and between the fourth region and the threaded bore,

the entire outer surface in the fifth region is exposed from the coating film.

17. The shell for an artificial joint according to claim 14,

the fourth region is adjacent to the spot facing.

18. A method for manufacturing a shell for an artificial joint, wherein,

the manufacturing method of the shell for the artificial joint comprises the following steps:

preparing a cup-shaped base;

disposing a first protective material so as to expose a part of an outer surface of the base and protect another part of the outer surface;

a first roughening step of forming a first rough surface portion on a portion exposed from the first protective material;

removing the first protective material; and

and a coating film forming step of forming a coating film containing a calcium phosphate material and an antibacterial material on the first rough surface portion and at least a part of the other portion of the outer surface.

19. The method of manufacturing a shell for a prosthetic joint according to claim 18,

after the step of removing the first protective material and before the step of forming the coating film,

the method for manufacturing the shell for the artificial joint further includes a second roughening step of forming a second rough surface portion on at least a part of the other portion of the outer surface.

20. The method of manufacturing a shell for an artificial joint according to claim 19,

after the process of removing the first protective material and before the second roughening process,

the method for manufacturing a shell for an artificial joint further includes a step of disposing a second protective material so as to expose a part of the other part of the outer surface and protect the other part of the outer surface,

in the second roughening step, a second rough surface portion is formed on the portion exposed from the second protective material.

21. The method of manufacturing an artificial joint shell according to claim 20,

after the second roughening process and before the coating film forming process,

the method of manufacturing the shell for a joint includes a step of removing the second protective material.

22. The method of manufacturing a shell for an artificial joint according to claim 21,

after the step of removing the second protective material and before the step of forming the coating film,

the method for manufacturing a shell for an artificial joint further includes a step of disposing a third protective material so that the first rough surface portion and a part of the second rough surface portion are exposed and the other part of the second rough surface portion and the outer surface are protected,

in the coating film forming step, the coating film is formed on a part of the first rough surface portion and the second rough surface portion exposed from the third protective material.

23. The method of manufacturing a shell for an artificial joint according to any one of claims 20 to 22,

disposing a second protective material so that the first rough surface portion is exposed in the step of disposing the second protective material,

in the second roughening step, the first roughened surface portion exposed from the second protective material is processed by a blasting method.

24. The method of manufacturing a shell for an artificial joint according to any one of claims 20 to 23,

a material having a higher heat resistance than the second protective material is used as the first protective material.

25. The manufacturing method of a shell for an artificial joint according to any one of claims 22 to 24,

the method for manufacturing the artificial joint shell comprises a step of arranging a third protective material so that the first rough surface part and a part of the second rough surface part are exposed and the other part of the second rough surface part and the outer surface are protected,

a material having a higher heat resistance than the third protective material is used as the first protective material.

26. The manufacturing method of a shell for an artificial joint according to any one of claims 22 to 25,

as the third protective material, a material having a higher heat resistance than the second protective material is used.

27. The manufacturing method of a shell for an artificial joint according to any one of claims 20 to 26,

using a first masking tape as the first protective material,

the step of disposing the first protective material further includes a step of attaching the first masking tape to another part of the outer surface so that a part of the outer surface is exposed.

28. The method of manufacturing an artificial joint shell according to any one of claims 20 to 27,

using a second masking tape as the second protective material,

the step of disposing the second protective material further includes a step of attaching the second masking tape to the remaining portion of the other portion of the outer surface so that a part of the other portion of the outer surface is exposed.

29. The manufacturing method of a shell for an artificial joint according to any one of claims 22 to 28,

using a third masking tape as the third protective material,

the step of disposing the third protective material further includes a step of attaching the third masking tape to the other part of the second rough surface portion and the outer surface so that a part of the second rough surface portion is exposed.

30. The manufacturing method of a shell for an artificial joint according to any one of claims 20 to 29,

the step of preparing the base includes a hole forming step of forming a hole in the base.

31. The method of manufacturing a shell for a prosthetic joint according to claim 30,

disposing a second protective material so as to expose a part of the other part of the outer surface and protect the other part of the outer surface;

a second roughening step of forming a second rough surface portion on the portion exposed from the second protective material; and

a step of disposing a third protective material so as to expose a part of the first rough surface portion and the second rough surface portion and protect the other part of the second rough surface portion and the outer surface,

in the first roughening process, edges of the hole are protected with the first protective material,

in the second roughening step, edges of the hole are exposed from the second protective material,

in the coating film forming step, the edge of the hole is exposed from the third protective material.

32. The manufacturing method of a shell for an artificial joint according to any one of claims 19 to 31,

the first roughening step is performed by at least one of a thermal spraying method and a blasting method.

33. The manufacturing method of a shell for an artificial joint according to any one of claims 19 to 32,

the second roughening step is performed by a blasting method.